arXiv subjects

Jiang-Tao Liu

Publications and source records attributed to Jiang-Tao Liu.

24 records · Page 2Linked to original sources

arXiv2013

On-board GRB trigger algorithms of SVOM-GRM

GRM (Gamma-Ray Monitor) is the high energy detector on-board the future Chinese-French satellite SVOM (Space-based multi-band astronomical Variable Object Monitor) which is dedicated to Gamma-Ray Burst (GRB) studies. This paper presents the investigation of the on-board counting rate trigger algorithms of GRM. The trigger threshold and trigger efficiency based on the given GRB sample are calculated with the algorithms. The trigger characteristics of GRM and ECLAIRs are also analyzed. In addition, the impact of solar flares on GRM is estimated, and the method to distinguish solar flares from GRBs is investigated.

astro-ph.IM↗

arXiv2012

Group delay of electromagnetic pulses through multilayer dielectric mirrors beyond special relativity

In this Letter, we investigate the group delay of optical pulses through multilayer dielectric mirrors (MDM) combined with gravitational wave (GW). We find that the delay increases linearly with MDM length for the transmitted wave packet, whereas the Hartman effect disappears. Our study provides insight into the nature of both quantum tunnelling and GW.

physics.optics↗

arXiv2011

The momentum-resolved and time-resolved two-color optical coherence absorption spectrum in the scattering process

The two-color optical coherence absorption spectrum (QUIC-AB) of GaAs quantum well in the presence of a charge current is investigated. We find that the QUIC-AB depends strongly not only on the amplitude of the electron current but also on the direction of the electron current. Thus, the amplitude and the angular distribution of scattering current in the scatter process can be detected directly in real time with the QUIC-AB. The phase shift of scattered waves and the details of the scattering potential can also be determined.

physics.optics↗

arXiv2011

The influence of the optical Stark effect on chiral tunneling in graphene

The influences of intense coherent laser fields on the transport properties of a single layer graphene are investigated by using the finite-difference time-domain method. Under an intense laser field, the valence band and conduction band states mix via the optical Stark effect. The chiral symmetry of Dirac electrons is broken and the perfect chiral tunneling is strongly suppressed.

cond-mat.other↗

arXiv2010

Effects of optical fields on the tunneling time of chiral electrons in graphene

The influences of optical fields on the tunneling time in graphene are investigated in real time using the finite-difference time-domain method. The tunneling time of electrons irradiated by an optical field is significantly different from that observed in traditional quantum tunneling. We found that when the barrier width increases, the group delay becomes constant for the reflected wave packet, but increases linearly for the transmitted wave packet. This peculiar tunneling effect can be attributed to current leakage in a time-dependent barrier generated via the optical Stark effect.

cond-mat.mes-hall↗

arXiv2007

Direct optical detection of pure spin current in semiconductors

We suggest a new practical scheme for the direct detection of pure spin current by using the two-color Faraday rotation of optical quantum interference process (QUIP) in a semiconductor system. We demonstrate theoretically that the Faraday rotation of QUIP depends sensitively on the spin orientation and wave vector of the carriers, and can be tuned by the relative phase and the polarization direction of the $ω$ and $2ω$ laser beams. By adjusting these parameters, the magnitude and direction of the spin current can be detected.

cond-mat.mes-hall↗